Depending on original color combination, other options, and if motor, trans, and rear end are matching originals, I'd guess I would top out around $3000, if the rot is not to bad and there is some paperwork to support it. See what the guy did to the 67SS in the latest Chevelle World from ACES. You are talking major bucks to restore, but if you don't mind taking your time, it might be fun. Also see the back of the Year One Chevelle catalog for a good discussion of car grading. Read it, grade the car, and then price other cars of the same grade around the country to see if you have a decent deal going. I paid $1750 for a Malibu that had a straight frame, good body and was in running condition. Salvaged what I could and am building a clone. I was not willing to start off with $5000 in a SS, then build the car that would end up not being a true SS anyway (I want my 502).
John Walker